Modern telecommunication systems, whether such systems are wireless or hard-wired, may be simultaneously accessed by multiple users having first been granted access. A key element in acquiring such access is that the user's equipment must have a valid identification code or number associated therewith. Using a cellular telephone network as an example, each individual cell phone is provided with a unique electronic serial number (ESN) which is “unalterable” and is installed in the cellular phone handset. In the past, the ESN has been programmed into an erasable programmable read only memory (EPROM), however, current Federal Communications Commission (FCC) rules specify that the ESN may not be stored in re-programmable memory or in any socketed device. Beyond that restriction, however, there is no requirement to prevent the field modification of an ESN.
In many cases, an ESN, acquired through unscrupulous or illicit methods, may be “cloned” into one or more cell phones. The cloned cell phones are then used fraudulently, the billable use of which is then charged to the legitimate owner of the ESN.
Storing an ESN in an unalterable memory does not provide security from fraudulent access to the cellular network. In some cases, the ESN memory may be removed, such as by desoldering, from the circuitboard of the handset, leaving the cell phone otherwise operable. The circuitboard terminals formerly occupied by the ESN memory chip may then be electrically coupled to an external circuit capable of providing counterfeit ESN(s). This type of fraudulent cell phone use may be avoided if the cellular phone circuit were rendered inoperative when the ESN memory is removed.
According to the FCC, the cellular industry estimates that carriers lose more than $150 million per year to cellular fraud. Thus, there is a clear need for providing a unique identification code (such as an ESN) to an external circuit (such as a cell phone) wherein the removal of the identification code providing means renders the external circuit inoperative.